• 한국철도학회논문집
• /
• 제9권1호
• /
• pp.29-35
• /
• 2006

Trains in LRT(Light Railway Transit) system usually have shorter car length than metro's because of their smaller passensers demand. Therefore it is very likely that the load condition of LRT system in abnormal operation, in case of which trains are in close proximity by system broke or train rescue works, could be worse rather than in normal operation, in spite of rare probability of abnormal operation. In this study, the target reliability indexes of several abnormal operations are estimated in accordance with the occurrence probabilities of each abnormal operation case and the reliability index of normal operation presented by the specification. From the indexes, load factors for the abnormal operation cases are estimated and the safety evaluation is performed for Yong-in LRT project.

• 한국물환경학회지
• /
• 제32권3호
• /
• pp.253-260
• /
• 2016

To reduce energy consumption in wastewater treatment plants (WWTPs), renewable energy applications such as small hydropower, solar energy, and wind energy are popular. However, it should be noticed that energy originated from operation of wastewater treatment process can be reduced through optimized operation based on analysis of factors affecting energy. In this research, the relationship to the various operational variables and influent factors was explored using correlation analysis and decision tree algorithm. Due to the non-linear characteristics of the process, it was difficult to find clear linear patterns through correlation analysis. However, decision tree algorithm showed its usefulness in uncovering hidden patterns that consume energy. As operational factors, influent flowrate, the amount of aeration, nitrate recycling pumping rate, and sludge wasting pumping rate were selected as important factors. For environmental factors associated with influent compositions and removal rate, BOD and T-N removal rate were selected as significant factors.

• 무역학회지
• /
• 제45권6호
• /
• pp.45-54
• /
• 2020

Occurrence of accidents at a container terminal results in casualties and damages of equipments which are involved in the accidents, and affects the terminal operation. Therefore, analyzing factors affecting occurrence of accidents at a container terminal is important for efficient operation of the terminal. Most of existing studies analyzing factors of accidents have performed in a land transportation field. And most of existing studies in a maritime field have focused on developing risk assessment methods, rather than identifying factors of accidents. This study aims to analyze the factors affecting the damage level which was resulted from accidents at a container terminal in Busan, Korea. After a basic statistical analysis of the accident dataset which was occurred in the terminal, a linear regression model is applied to identify the factors which affect the damage level resulted from the accident. As a result of analysis, it is found that the more number of equipments, facilities and containers damaged from the accidents positively affect the damage level from the accidents, as well as dozing during working. The results of this study are expected to be a basic for developing safety management.

• 한국화재소방학회논문지
• /
• 제34권4호
• /
• pp.115-124
• /
• 2020

본 연구에서는 소방공무원의 안전과 회복탄력성 향상을 위한 재난현장 소방공무원 회복실 운영모델을 제공하고자 한다. 이를 위하여 해외의 운영사례 및 선행연구의 회복실 운영 관련 요소들을 분석하여 관리적 요인과 운영 인력적 요인, 설비적 요인, 접근성 및 편의성 요인 등으로 분류하고, 상대적 중요도를 측정하였으며, 분야별 중요도의 하위 계층에 대한 중요도를 측정하여 재난현장 소방공무원 회복실 운연을 위한 항목들의 우선순위를 파악하였다. 전문가 분석을 실시한 결과 재난현장 회복실 운영에서 운영 인력적 요인이 가장 중요한 것으로 나타났으며, 접근성 및 편의성 요인, 관리적 요인, 설비적(비품) 요인, 설비적(장비) 요인의 순으로 나타났다. 이를 기반으로 재난현장 회복실 운영 가이드라인을 제안하였다.

• 상하수도학회지
• /
• 제32권6호
• /
• pp.535-550
• /
• 2018

Total organic carbon (TOC) will replace chemical oxygen demand ($COD_{Mn}$) as an effluent water quality standard in public sewage treatment works (PSTWs) from 2021 in Korea. To ensure effective control of TOC in the effluent, investigation was carried out into TOC levels and sewage treatment operation factors in five target PSTWs using anaerobic-anoxic-aerobic ($A_2O$) processes, media, membrane, and sequencing batch reactor (SBR) technologies. TOC removal efficiencies appeared to be 93-96% on average. As a fraction of TOC, biodegradable dissolved organic carbon (BDOC) was reduced from 64% in the influent to 9% in the effluent in these PSTWs. During the investigation, biological treatment processes were applied flexibly for operation factors such as HRT, SRT, MLSS, F/M ratios and BOD volume loads, based on the influent characteristics and design conditions. As a result, we suggest efficient operating conditions in PSTWs by evaluating relationships between TOC removal and operation factors.

• 디지털산업정보학회논문지
• /
• 제18권2호
• /
• pp.93-110
• /
• 2022

The purpose of this study is to explore business investment and operation of O2O (Online-To-Offline) combined service. The study will analyze the necessary factors for growing the business by dividing the O2O service by industry. The Online-to-Offline is a method of inducing purchases of products and services by connecting between online and offline This research methodology organized the four stages of the analysis process. The analysis of all stages was performed with association rules in big data techniques. It is divided into the start-up period, growth period, maturity period, and decline period, and analysis is conducted on the business investment, expenditure cost, business operation, and conflict factors. As the research result, the first analysis has shown commonality with government subsidies, bank loans, and personal funds in all industries. The second analysis showed a lot of expenditure on labor costs of internal employees, marketing/sales, facility facilities, equipment, and equipment purchase costs. The third analysis showed difficulty in raising the investment resources necessary for business operations in all industries. The last analysis showed conflicts in the industry, businesses license, legal systems, and small business owners in all industries. This study contributed to the abundance and diversity of research methodologies in management information systems using association rules. In addition, the description of organizational development theory was updated while explaining the business investment and operation of O2O combined services. In practical implication, the O2O services include environmental factors that cause convergence between industries. Accordingly, this is required for new O2O services through new laws and systems and reorganization of existing laws and regulations.

• Journal of Korea Trade
• /
• 제27권3호
• /
• pp.65-86
• /
• 2023

Purpose - As globalization progresses, complexity also increases, and various factors that threaten port functions are emerging. Accordingly, the demand for port security to prevent the crisis and resilience that quickly recovers its original function after the crisis is also increasing in port operations. However, few studies have examined how to ensure the port security and how the resilience affects operation performance of port and sustainability performance as well. So the study aims to find out how port security affects port resilience and port operational performance, and consequently, this two factors affect socioeconomic and environmental sustainability performance respectively and synthetically. Design/methodology - Confirmatory Factor Analysis (CFA) was first performed to determine the validity of the factors of model and hypothesis test was performed using Structural Equation Model (SEM) to analyze the Port Performance Model, which show the perception logic among port security level, port resilience, operation performance, and sustainability performance. In order to empirically analyze this model, total 264 respondents from port security operators, shipping companies in South Korea were surveyed. Findings - As result of SEM, First, port security level positively affected the resilience (H1) and cargo operational performance (H2) but not in both of the sustainability performances (H3, H4). Second, resilience positively affected only cargo operational performance (H5) and socio-economic sustainability performance (H7). Last, cargo operation performance positively affects the both of sustainability performances (H8, H9). Originality/value - It was confirmed that port security could improve cargo operational performance through ensuring port resilience and eventually increase the socio-economic sustainability. Therefore the study implies that careful integration and management of port security, port resilience, and sustainability are required, along with compromise on sustainable development goals in the social, economic, and environmental area among all stakeholders.

• 간호행정학회지
• /
• 제22권5호
• /
• pp.415-423
• /
• 2016

Purpose: The purpose of this research was to provide patients with safe preoperative preparatory procedures by removing any risk factors from the preparatory procedures by using failure mode and effects analysis, which is a prospective risk-managing tool. Methods: This was a research design in which before and after conditions of a single group were studied, Failure mode and effects analysis were applied for the preparatory procedures done before operations. Results: The preparation omission rate before the operation decreased from 2.70% to 0.04%, and operation cancellation rate decreased from 0.48% to 0.08%. Conclusion: Failure mode and effects analysis which remove any risk factors for patients in advance of the operation is effective in preventing any negligent accidents.

• 한국항공운항학회지
• /
• 제16권4호
• /
• pp.35-40
• /
• 2008

There are many studies indicate that human is one of the major contributing factors to the aviation accident. To this end, the Human Factor of pilots and in flight operations has been a popular subject to be studied, however, not of the air traffic controllers. Recently, some States have started studying Human Errors in Air Traffic Control field, removal of the potential errors in advance and prevention of the similar errors. This study analyzed Human Errors in air traffic control in terms of LOSA of airlines, which has been actively studied. This study will contribute to safe Flight Operation and Air Traffic Control.

• 수산해양교육연구
• /
• 제19권3호
• /
• pp.346-354
• /
• 2007

Recently, the efficient planning and operations of container terminals have become essential problems to develop the evaluation method with operational rules. Container terminals are required to have enough berths and container yards as well as various equipments and facilities, but in reality there are many differences in their resources owing to the circumstances of each terminal. This study introduces a simulation model for evaluating various operation rules for improving the performance of transshipment container terminal operations. This model can analysis various factors (throughputs, utilizations etc) and shows operational alternative considering design factors of transshipment container terminal with the related circumstances.